Curling stone



Nov. 23, 1948. J, TURN ULL 2,454,492

CURLING STONE Filed Dec. 26, 1946- INVENTOR WILLIAM JAMES TURNBULL A TORNEY Patented Nov. 23, 1948 CURLING STONE William James Turnbull, West Vancouver, British Columbia, Canada Application December 26,1946, Serial No. 718,494

3 Claims.

My invention relates to improvements in curlplay a game similar to curling, which rocks are designed to travel a relatively low speed and keep in motion for a relatively long time, finally coming to rest very slowly.

The objects of the present invention are to provide such a device popularly referred to as a rock where the action of each so-called rock will be similar when each of said rocks is projected across a playing surface under similar force and condition, in other words, to provide such accuracy in function that an experienced player will know exactly what result he can expect from a shot irrespective of the rock that he may be using.

The structure here contemplated is designed to prevent warpage or distortion of frictional areas incidental to climatic conditions; to provide a weight constant of the structure, and to provide for friction areas which are not subject to measurable variation incidental to wear, as will he more fully described in the following specification and shown in the accompanying drawings, in which- Fig. 1 is a perspective view of the invention.

Fig. 2 is a part sectional and part elevational view.

In the drawings like characters of reference indicate corresponding parts in each figure.

The numeral I indicates a casing which is preferably of moulded material and consists of a cup shaped lower section 2 and an upper section 3, between which a heavy ball'd, preferably a steel bearing ball, is enclosed. The lower section 2 is provided with a central opening which is of a diameter slightly greater than that part of the ball t, which when the rock is upon a playing surface, lies in the plane of the marginal edge of said opening, but small enough to prevent said ball from projecting appreciably below the plane of the base of the lower section. A drop of in a rock having a 2 /4" ball is the preferred projection of the ball below said plane when the device is lifted by its casing. The upper section is provided with a central opening I which is similarly slightly greater in diameter than the ball at the plane of said opening, as shown in Figure 2.

A meridian bearing 9 is provided for the ball in the form of an annulus having a centrally disposed horizontal rib lt about its outer periphery to define lower and upper rebates H and 12 in which the adjacent peripheral rims of the lower and upper casing sections 2 and 3 are respectively secured. The bearing 9 is preferably made of a non-abrasive material. Thin veneer plywood has been found satisfactory, since by virtue of the alternating grain direction of the several, lamina tions or veneers, the periphery of said baring remains a true circle. The bearing diameter is very slightly larger than the ball and since it is not subject to distortion due to warpage or shrinkage, the drag of the casing on the ball when the rock is moving under its own momentum along a playing surface will be constant and its direction and deceleration can be accurately gauged. The bearing 9 serves as a structural rib to reinforce the casing I against distortion incidental to impact as well as providing a bearing media of light weight and one which will retain its shape and diameter almost indefinitely, so that the frictional drag upon the ball when the device is in play will be substantially constant, irrespective of the position of ball contact with the periphery of said bearing.

The outer peripheral edges of the lower and upper casing members are rebated as at l4 and [5 respectively, so that when these casing members and the bearing 9 are secured in juxtaposition as shown in Figure 2, said rebates and the rib l8 form an annular groove in which a circular resilient bumper i6 is provided to reduce the shock and noise resulting from two rocks coming into contact with each other when in play. It will be seen that from the moment a rock is brought into contact with a playing surface, the contact between the ball and casing i will be at a point on the inner periphery of the bearing 9 and when in rotating, bias is put on the ball, the point of contact will obviously move around said periphery and as the assembled casing is of very light weight the wear upon said hearing will be almost imperceptible.

What I claim as my invention is:

1. An amusement device adapted for use on a playing surface, said device comprising a hollow circular casing having a peripheral wall and supporting a horizontal bearing, a ball freely journalled within the bearing, said bearing being disposed to contact the ball about its greater horizontal circle and to extend outwardly to the peripheral wall of the casing, said casing having a bottom opening of a diameter to allow the ball to rest in rolling contact with the playing surface when the casing is in contact therewith, said 4 bearing serving to prevent the ball from engaging any part of the periphery of said opening when so placed.

2. An amusement device adapted for use on a playing surface, said device comprising a hollow casing having a peripheral wall and formed of lower and upper sections, the lower section having an opening concentric with the vertical axis of said casing, a ball freely enclosed within the casing, said ball being adapted to project through the opening to rest in rolling contact with the playing surface'when said casing is placed upon said playing surface and a bearing disposed to surround the ball about its horizontal axis and extend outwardly to the peripheral wall of the casing, said bearing being of laminated material wherein the grain of one lamination is disposed in angular relation to that of an'adjoining'lamination.

3. An amusement device adapted'for use on a playing surface, said device comprising a thin walled cup shaped lower section of moulded material having a bottom opening, a concavo convex upper section having an opening and adepending wall, both of saidopenings being concentric with the vertical axis of the casing, a bearing connecting the lower and upper sections and extending inwardly therefrom, a heavy ball freely journalled in the bearing, said ball being adapted to project through the bottom section opening to bear upon the playing surface when the casing is in contact with said surface.

WILLIAM JAMES TURNBULL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,849,414 Turnbull Mar. 15, 1932 FOREIGN PATENTS- Number Country Date 25,092 Great Britain Nov. 15, 1902 161,372 Great Britain Apr. 14, 1921 

